This is a competitive renewal for our longstanding Training Program in Diabetes, Endocrinology and Metabolic Diseases. During the most recent funding cycle, about 5 postdoctoral fellows were supported each year. A total of 13 trainees working in 10 different labs have been supported. The program is designed to accommodate both Ph.D. scientists as well as physician scientists with M.D. or M.D, Ph.D. degrees, of whom most enter through the Penn Clinical Fellowship Program in Endocrinology, Diabetes and Metabolism. Of the 13 postdoctoral trainees supported by this T32 during the last period, 8 have "graduated" while 5 are currently supported. One of the fellows who gave up the training grant had to do so prematurely due to an unexpected need to leave the country. Of the other seven, three have obtained independent KO8 funding and are presently Instructors in Medicine at the University of Pennsylvania School of Medicine. Two have returned to the clinic with plans to continue research following training in Clinical Endocrinology, one has obtained independent funding through the individual NRSA mechanism, and one has taken a position in private industry. We ask for a continuation of support for five fellows per year, anticipating that most fellows will receive two years of funding, though some one or three. For the next period, we request additional support to allow one of these five fellows to undertake specialized training in Clinical Epidemiology related to diabetes or endocrinology as part of a new program that integrates this training grant with the University of Pennsylvania Masters of Clinical Epidemiology Program. We also request, for the first time, sufficient funds to support three predoctoral students working in the areas of this program during their third through fifth years of graduate school. At present, there are in laboratories directed by our trainers 36 students working towards their Ph.D. theses, the majority focusing on problems relevant to the mission of this T32 and unsupported by training grants. Six (17%) are underrepresented minorities. Our 25 training faculty have primary appointments in nine Medical School Departments and consist of 15 professors, 7 associate professors, and assistant 3 professors. Six members of the training faculty are woman and one is African- American. The significant expansion in the number of mentors relates primarily to the institution of the training track in Clinical Epidemiology. However, two faculty members new to Penn have also been appointed to the training grant. Training grant faculty bring to the program expertise in p-cell development and function, hormone action, physiology, diabetic complications, genetics in humans and model organisms, transcriptional regulation, patient oriented research, epidemiology and biostatistics. This training program continues to provide superb preparation for those scientists committed to careers in research into diabetes, endocrinology and metabolism.